RELIABILITY OF STANDARD FOOT RADIOGRAPHIC MEASUREMENTS

Fifty standing dorsoplantar and lateral foot radiographs were obtained on a consecutive series of patients seen in an orthopaedic foot and a nkle clinic. These radiographs were duplicated, and eight common foot measurements were made on each pair by six experienced examiners. Meas urements were made in two ways: first by a subjective visual assessmen t, and second by quantitative evaluation made according to strictly de fined criteria. All measurements were made under controlled, ideal con ditions with similar high quality goniometers. The results demonstrate d overall greater reliability in the quantitative methods than the non -quantitative methods. For each of the quantitative techniques, a cumu lated frequency distribution of differences between examiners was calc ulated. The approximate 95% bounds for these measures were: hallux-met atarsophalangeal angle = 6-degrees, first intermetatarsal angle = 4-de grees, metatarsophalangeal-5 angle = 11-degrees, fourth intermetatarsa l angle = 4-degrees, AP talocalcaneal angle = 20-degrees, lateral talo calcaneal angle = 12-degrees, seasamoid station = 2 grades, and forefo ot width = 5 mm. Physicians using these parameters to make decisions r egarding patient care and clinical outcomes need to keep in mind these potential errors in making foot radiographic measurements.